NSF ESH Program
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PARCS Science Highlights
Reindeer antlers reveal a
history of environmental change in Franz Josef Land, Russia (cont.).
A primary tool used by PARCS researchers to decipher climates of the
past is the well-dated evidence left by biological organisms that are
adapted to particular environmental settings. Range extensions of mammals
such as reindeer (Rangifer tarandus) are a clear indication of
warmer climate in the early Holocene. PARCS researchers visited the Franz
Josef Land archipelago in arctic Russia over several field seasons, and
systematically surveyed the unglaciated areas of numerous islands (Figure
1). They found numerous shed reindeer antlers, often on raised beaches
and emerging from melting snowdrifts, which will preserve them longer.
From these collected specimens, small samples from individual antlers
were submitted for radiocarbon dating.
Figure 1. Map of the Franz Josef Land archipelago, with green shading
indicating non-glaciated terrain.
Twenty-six of the antlers were dated, yielding ages between 6400 and
1300 years ago (Figure 2). Because the oldest specimens were not well
preserved, the age of first appearance could be constrained only as older
than 6400 years ago. In contrast, the number and preservation of the youngest
samples provides a much more precise constraint for the extirpation of
reindeer from Franz Josef Land. Analysis determined a 50% to 95% probability
that reindeer were gone somewhere between 110 and 500 years after the
last dated antler. This timing matches the most prominent expansion of
glaciers for the last 10,000 years in Franz Josef Land (Figure 3), which
began between 1500 and 1000 years ago. When the glaciers expanded, and
snow remained on the ground longer, forage was reduced for the reindeer
and they likely died off or moved southward.
Figure 2. Histogram of the age distribution of shed antler specimens
from Franz Josef Land.
Figure 3. Time series of reindeer occurrence for Franz Josef Land from
radiocarbon dating of antler remains compared to the glaciation record
for Franz Josef Land and climate records from Svalbard (Forman et
al., 2000; modified from Lubinski et al., 1999).
The island of Svalbard, south and west of Franz Josef Land,
still supports a population of reindeer and can serve as an analogy for
early Holocene conditions farther north. With only 15% of the land area
unglaciated in Franz Josef Land, approximately 2500 square kilometers
is available for vegetation growth. Comparison with the land area of Svalbard
and its present population of 10,000 to 11,000 reindeer, it appears that
only very small numbers (240 to 733) of reindeer would have been able
to find sufficient forage in Franz Josef Land in the best of conditions.
When summer temperatures were warmer by 1-4°C in the early Holocene,
reindeer would have thrived on Svalbard, and herd size may have expanded
beyond available resources. Migration to marginal areas like Franz Josef
Land would have been driven by population pressure, and reindeer could
have traveled over sea ice in the winter, or swam part of the way in spring,
to reach uninhabited terrain. With late twentieth-century warming occurring
in the arctic, it is possible that the glaciers may again retreat in and
summer snowcover may decrease in Franz Josef Land, perhaps allowing the
reindeer to once again immigrate to this and similar high arctic regions.
A full text PDF
version of this Reindeer research paper is available for those with online
access to the journal The
Holocene.
References:
Forman, Steven L., Lubinski, David, and Weihe, Richard (2000). The Holocene
occurrence of reindeer on Franz Josef Land, Russia. The Holocene
10, 763-768.
Lubinski, D. J., Forman, S. L., and Miller, G. H., 1999, Holocene glacier
and climate fluctuations on Franz Josef Land, Arctic Russia, 80°N.
Quaternary Science Reviews 18, 85-108.
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